Social media sites are likely to have one hour to remove terrorist content in rules being drafted by the European Union, according to the Financial Times.
 
Removal of such content in an hour is currently voluntary, but draft rules by the European Commission (the executive arm of the EU) that would force companies to remove it within that timeframe are set to be published next month, the newspaper reported.
 
Companies such as Facebook, YouTube and Twitter would have to remove the content within an hour of it being flagged as illegal by police and law enforcement bodies. The draft regulation would apply to websites of all sizes, according to the EU's Commissioner for Security Julian King. He said that policies for the removal of videos and other posts were not always clear, telling the FT: "All this leads to such content continuing to proliferate across the internet, reappearing once deleted and spreading from platform to platform."
 
The EU has previously said that illegal content is particularly damaging when it is first published. "Terrorist content is most harmful in the first hours of its appearance because of its fast spreading and entails grave risks to citizens and society at large," it stated on its website in March, as it tightened its voluntary guidelines.
 
YouTube said it was not commenting on the draft regulation, while Facebook and Twitter had not responded to CNBC's requests for comment at the time of publication.